Most Internet scams target people who are naive, gullible, and quick to believe that what they see is what they're going to get. For example, there's this app going around called the Facebook Hacker Pro that can supposedly get you access to any Facebook account, just by inputting an email address, ID, or name.
When you've entered the requested information of your target, all you have to do is click "Crack Password" and let the app work its magic. If you're sharp, you'll know by now that no software exists that can do what this app claims to be able to do.
The fake Facebook password cracker was discovered by security experts from Trend Micro. It poses as a free app, up until you actually try to obtain the password. A message then displays asking the user to pay $29.99 as a license fee to continue using the app. Those who actually fork over the cash are then shown a list of passwords, but not the ones they were expecting.
The program downloads and uses a free third party application, designed to recover and display saved passwords in the users’ local browser cache. Thus, the retrieval of the credentials will only work for users who have passwords stored in their systems.
-- Roddell Santos, Trend Micro threats analyst
The app has been identified as SPYW_FAKEHACK, and carries with it a malicious toolbar app identified as ADW_PLUGIN. In short, it's a useless app if you're trying to carry out an equally malicious intent of trying to hack into someone else's Facebook account.
If you're trying to use the app to recover your own password, then it's still a pretty foolish thing to do, considering you can actually do that without the use of any app.